PROBLEM TO BE SOLVED: To provide a ruminant controlling method in which the lower jaw movements of a ruminant associated with the behaviors of feeding, rumination, drinking or the like can be detected by a simple mechanism and can be easily transmitted to the outside.SOLUTION: A ruminant controlling method for controlling the behaviors of a ruminant includes: a step of obtaining movement information on the jaws which is outputted from a device attached to a peripheral part of the mouth of a ruminant according to a bending quantity generated by the jaw movements of the ruminant a step of obtaining inclination information on the head outputted from a device attached to the head of the ruminant according to an inclination quantity generated by the inclination of the head of the ruminant and a step of discriminating among the ruminant behaviors of feeding, rumination, drinking, and resting based on the movement information on the jaws and the inclination information on the head of the ruminant.
